/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "recovery_utils/roots.h"

#include <fcntl.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>

#include <iostream>
#include <string>
#include <vector>

#include <android-base/logging.h>
#include <android-base/properties.h>
#include <android-base/stringprintf.h>
#include <android-base/unique_fd.h>
#include <cryptfs.h>
#include <ext4_utils/wipe.h>
#include <fs_mgr.h>
#include <fs_mgr/roots.h>

#include "otautil/sysutil.h"

// HUANGLONG begin
#include <sys/mount.h>
#include <linux/fs.h>
#include <dirent.h>
#include "otautil/copyfile.h"
// HUANGLONG end

using android::fs_mgr::Fstab;
using android::fs_mgr::FstabEntry;
using android::fs_mgr::ReadDefaultFstab;

static Fstab fstab;

// HUANGLONG begin
#define DEV_DIR "/dev/block/"
#define DEV_MOUNTPOINT "/sdcard/"
#define SDCARD_MOUNTPOINT   "/sdcard"
#define MAX_DEV_NAME_LENGTH 64
#define MAX_RETRY_TIMES     10

static const char* FS_TYPES[] = {
  "vfat",
  "ntfs",
  "ext4",
  "tntfs",
  nullptr,
};

enum {
  //NAND_TYPE,
  EMMC_TYPE,
  NULL_TYPE
};

// Check the flash type.
int check_flash_type() {
  int ret = NULL_TYPE;
  char buffer[1024];
  FILE *fp;
  fp = fopen("/proc/cmdline","r");
  if (fp != NULL) {
    if (fgets(buffer,1024,fp) != NULL) {
      if (strstr(buffer,"mmcblk")) {
        ret = EMMC_TYPE;
      } else {
        LOG(ERROR) << "check_flash_type, can't get Flash Type in Cmdline " << buffer;
      }
    }
    fclose(fp);
  }
  return ret;
}

// Clearing Partitions
int write_emmc_clean(const char* partition) {
  Volume* vblock = volume_for_mount_point(partition);
  if (vblock == NULL) {
    printf("can't find mount point: %s", partition);
    return -1;
  }
  LOG(INFO)<< "write_clean" << vblock->blk_device.c_str() << "begin\n";
  FILE* fw = fopen(vblock->blk_device.c_str(), "wb");
  if (fw == NULL) {
    printf("can't fopen %s: %s", partition,strerror(errno));
    return -1;
  }
  int fw_fd = fileno(fw);
  unsigned char readbuf[32*1024];
  ssize_t n = 0;
  while (n != -1) {
    memset(readbuf, 0xff, sizeof(readbuf));
    n = write(fw_fd, readbuf, sizeof(readbuf));
  }
  fclose(fw);
  return 0;
}

// Clearing Partitions in EMMC_TYPE
int write_clean(const char* partition) {
  LOG(INFO)<< "write_clean" << partition << "begin\n";
  int ret = -1 ;
  if (check_flash_type() == EMMC_TYPE) {
    ret = write_emmc_clean(partition);
  }
  return ret;
}

// Write a specified partition, eg: /baseparam
int write_partition(const char* partitionMountPath, const char* fileToWrite) {
    Volume* vblock = volume_for_mount_point(partitionMountPath);
    if (vblock == NULL) {
        printf("can't find mount point: %s", partitionMountPath);
        return -1;
    }
    return copyFile(fileToWrite, vblock->blk_device.c_str());
}

// Wait for the device. The query is performed once every second for 10 times.
static void wait_for_device(const char* fn) {
  int tries = 0;
  int ret = 0;
  struct stat buf;
  do {
      ++tries;
      ret = stat(fn, &buf);
      if (ret) {
        LOG(ERROR) <<"stat "<<fn<<" try "<<tries<<": "<<strerror(errno);
        sleep(1);
      }
  } while (ret && tries < MAX_RETRY_TIMES);

  if (ret) {
    LOG(ERROR) <<"faile to stat "<<fn;
  }
}

static int update_volume_by_dir(const char *dir_buf,const char *vf_type) {
  if (fstab.empty()) {
    LOG(ERROR) << "can't update_volume_by_dir: no fstab loaded";
    return -1;
  }
  if (dir_buf == NULL || vf_type == NULL) {
    LOG(ERROR) << "can't update_volume_by_dir: dir_buf == NULL || vf_type == NULL";
    return -1;
  }
  for (FstabEntry& entry : fstab) {
    LOG(INFO) << "update_volume_by_dir, entry is " << " " << entry.mount_point << " "
              << " " << entry.fs_type << " " << entry.blk_device << " ";
    if (entry.mount_point == SDCARD_MOUNTPOINT) {
      // if (entry.blk_device.c_str() != NULL) {
      //   free((void *)entry.blk_device.c_str());
      // }
      LOG(INFO) << "update_volume_by_dir, dir_buf is ["<< dir_buf <<
                "], and vf_type is ["<< vf_type << "]";
      entry.blk_device = dir_buf; // std::string(dir_buf);
      entry.fs_type = vf_type; // std::string(vf_type);
      LOG(INFO) << "update_volume_by_dir, the new sdcard device is ["<< entry.blk_device <<
                "], and the new fstype is ["<< entry.fs_type << "]";
      return 0;
    }
  }
  return -1;
}

static int mount_device(const char *dev, const char *mount_point, int *type_index)
{
  int fs_types = sizeof(FS_TYPES) / sizeof(FS_TYPES[0]);
  int i = 0, ret = -1;

  for (i = 0; i < fs_types - 1; i++) {
    LOG(INFO) << "try mount " << dev << " to " << mount_point << " with fs type " << FS_TYPES[i];
    ret = mount(dev, mount_point, FS_TYPES[i], MS_NOATIME | MS_NODEV | MS_NODIRATIME, "");
    if (ret == 0) {
      *type_index = i;
      break;
    }
    LOG(INFO) << "try mount " << dev << " to " << mount_point << " with fs type " << FS_TYPES[i] << ", strerror(errno):" << strerror(errno);
  }

  LOG(INFO) << (ret ? "failed" : "success") << ", ret = " << ret;
  return ret;
}

int update_volume(const char *dev) {
  int ret = -1;
  if (umount(DEV_MOUNTPOINT)) {
    LOG(ERROR) << "1st umount failed " << dev;
  }

  int type_index = 0;
  if (mount_device(dev, DEV_MOUNTPOINT, &type_index)) {
    return -1;
  }

  sync(); // after mount, sync file system

  ret = access("/sdcard/update.zip", F_OK);
  if (umount(DEV_MOUNTPOINT)) {
    LOG(ERROR) << "2nd umount failed " << dev;
  }

  if (ret == 0) {
    LOG(INFO) << "find update.zip in" << dev;
    LOG(INFO) << "vf_type is " << FS_TYPES[type_index];
    ret = update_volume_by_dir(dev, FS_TYPES[type_index]);
    LOG(INFO) << "update_volume_by_dir, ret = " << ret;
    return 0;
  }

  LOG(ERROR) << "there is no update.zip in " << dev << " return ret=" << ret;
  return -2;
}

int update_volume_with_devpath(const char *devpath)
{
  wait_for_device(devpath);
  if (update_volume(devpath) != 0) {
    return -1;
  }
  return 0;
}

// Mounting a USB flash drive
int find_upzip_and_update_volume() {
  int ret = -1;
  char dir_buf[256] = {0};
  struct dirent *dirent;

  LOG(INFO) << "find update.zip ";
  wait_for_device("/dev/block/sda");
  DIR * dir = opendir(DEV_DIR);
  if (dir == nullptr) {
    return -1;
  }

  while ((dirent = readdir(dir))) {
    if (strstr((dirent->d_name), "sd")) {
      strcpy(dir_buf, DEV_DIR);
      strcat(dir_buf, dirent->d_name);
      ret = update_volume(dir_buf);
      if (ret == 0) {
        break;
      } else {
        continue;
      }
    }
  }

  closedir(dir);
  return ret;
}
// HUANGLONG end

constexpr const char* CACHE_ROOT = "/cache";

void load_volume_table() {
  if (!ReadDefaultFstab(&fstab)) {
    LOG(ERROR) << "Failed to read default fstab";
    return;
  }

  fstab.emplace_back(FstabEntry{
      .blk_device = "ramdisk",
      .mount_point = "/tmp",
      .fs_type = "ramdisk",
      .length = 0,
  });

  std::cout << "recovery filesystem table" << std::endl << "=========================" << std::endl;
  for (size_t i = 0; i < fstab.size(); ++i) {
    const auto& entry = fstab[i];
    std::cout << "  " << i << " " << entry.mount_point << " "
              << " " << entry.fs_type << " " << entry.blk_device << " " << entry.length
              << std::endl;
  }
  std::cout << std::endl;
}

Volume* volume_for_mount_point(const std::string& mount_point) {
  return android::fs_mgr::GetEntryForMountPoint(&fstab, mount_point);
}

// Mount the volume specified by path at the given mount_point.
int ensure_path_mounted_at(const std::string& path, const std::string& mount_point) {
  return android::fs_mgr::EnsurePathMounted(&fstab, path, mount_point) ? 0 : -1;
}

int ensure_path_mounted(const std::string& path) {
  // Mount at the default mount point.
  return android::fs_mgr::EnsurePathMounted(&fstab, path) ? 0 : -1;
}

int ensure_path_unmounted(const std::string& path) {
  return android::fs_mgr::EnsurePathUnmounted(&fstab, path) ? 0 : -1;
}

static int exec_cmd(const std::vector<std::string>& args) {
  CHECK(!args.empty());
  auto argv = StringVectorToNullTerminatedArray(args);

  pid_t child;
  if ((child = fork()) == 0) {
    execv(argv[0], argv.data());
    _exit(EXIT_FAILURE);
  }

  int status;
  waitpid(child, &status, 0);
  if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
    LOG(ERROR) << args[0] << " failed with status " << WEXITSTATUS(status);
  }
  return WEXITSTATUS(status);
}

static int64_t get_file_size(int fd, uint64_t reserve_len) {
  struct stat buf;
  int ret = fstat(fd, &buf);
  if (ret) return 0;

  int64_t computed_size;
  if (S_ISREG(buf.st_mode)) {
    computed_size = buf.st_size - reserve_len;
  } else if (S_ISBLK(buf.st_mode)) {
    uint64_t block_device_size = get_block_device_size(fd);
    if (block_device_size < reserve_len ||
        block_device_size > std::numeric_limits<int64_t>::max()) {
      computed_size = 0;
    } else {
      computed_size = block_device_size - reserve_len;
    }
  } else {
    computed_size = 0;
  }

  return computed_size;
}

int format_volume(const std::string& volume, const std::string& directory) {
  const FstabEntry* v = android::fs_mgr::GetEntryForPath(&fstab, volume);
  if (v == nullptr) {
    LOG(ERROR) << "unknown volume \"" << volume << "\"";
    return -1;
  }
  if (v->fs_type == "ramdisk") {
    LOG(ERROR) << "can't format_volume \"" << volume << "\"";
    return -1;
  }
  if (v->mount_point != volume) {
    LOG(ERROR) << "can't give path \"" << volume << "\" to format_volume";
    return -1;
  }
  if (ensure_path_unmounted(volume) != 0) {
    LOG(ERROR) << "format_volume: Failed to unmount \"" << v->mount_point << "\"";
    return -1;
  }
  if (v->fs_type != "ext4" && v->fs_type != "f2fs") {
    LOG(ERROR) << "format_volume: fs_type \"" << v->fs_type << "\" unsupported";
    return -1;
  }

  bool needs_casefold = false;
  bool needs_projid = false;

  if (volume == "/data") {
    needs_casefold = android::base::GetBoolProperty("external_storage.casefold.enabled", false);
    needs_projid = android::base::GetBoolProperty("external_storage.projid.enabled", false);
  }

  // If there's a key_loc that looks like a path, it should be a block device for storing encryption
  // metadata. Wipe it too.
  if (!v->key_loc.empty() && v->key_loc[0] == '/') {
    LOG(INFO) << "Wiping " << v->key_loc;
    int fd = open(v->key_loc.c_str(), O_WRONLY | O_CREAT, 0644);
    if (fd == -1) {
      PLOG(ERROR) << "format_volume: Failed to open " << v->key_loc;
      return -1;
    }
    wipe_block_device(fd, get_file_size(fd));
    close(fd);
  }

  int64_t length = 0;
  if (v->length > 0) {
    length = v->length;
  } else if (v->length < 0 || v->key_loc == "footer") {
    android::base::unique_fd fd(open(v->blk_device.c_str(), O_RDONLY));
    if (fd == -1) {
      PLOG(ERROR) << "format_volume: failed to open " << v->blk_device;
      return -1;
    }
    length = get_file_size(fd.get(), v->length ? -v->length : CRYPT_FOOTER_OFFSET);
    if (length <= 0) {
      LOG(ERROR) << "get_file_size: invalid size " << length << " for " << v->blk_device;
      return -1;
    }
  }

  if (v->fs_type == "ext4") {
    static constexpr int kBlockSize = 4096;
    std::vector<std::string> mke2fs_args = {
      "/system/bin/mke2fs", "-F", "-t", "ext4", "-b", std::to_string(kBlockSize),
    };

    // Project ID's require wider inodes. The Quotas themselves are enabled by tune2fs on boot.
    if (needs_projid) {
      mke2fs_args.push_back("-I");
      mke2fs_args.push_back("512");
    }

    if (v->fs_mgr_flags.ext_meta_csum) {
      mke2fs_args.push_back("-O");
      mke2fs_args.push_back("metadata_csum");
      mke2fs_args.push_back("-O");
      mke2fs_args.push_back("64bit");
      mke2fs_args.push_back("-O");
      mke2fs_args.push_back("extent");
    }

    int raid_stride = v->logical_blk_size / kBlockSize;
    int raid_stripe_width = v->erase_blk_size / kBlockSize;
    // stride should be the max of 8KB and logical block size
    if (v->logical_blk_size != 0 && v->logical_blk_size < 8192) {
      raid_stride = 8192 / kBlockSize;
    }
    if (v->erase_blk_size != 0 && v->logical_blk_size != 0) {
      mke2fs_args.push_back("-E");
      mke2fs_args.push_back(
          android::base::StringPrintf("stride=%d,stripe-width=%d", raid_stride, raid_stripe_width));
    }
    mke2fs_args.push_back(v->blk_device);
    if (length != 0) {
      mke2fs_args.push_back(std::to_string(length / kBlockSize));
    }

    int result = exec_cmd(mke2fs_args);
    if (result == 0 && !directory.empty()) {
      std::vector<std::string> e2fsdroid_args = {
        "/system/bin/e2fsdroid", "-e", "-f", directory, "-a", volume, v->blk_device,
      };
      result = exec_cmd(e2fsdroid_args);
    }

    if (result != 0) {
      PLOG(ERROR) << "format_volume: Failed to make ext4 on " << v->blk_device;
      return -1;
    }
    return 0;
  }

  // Has to be f2fs because we checked earlier.
  static constexpr int kSectorSize = 4096;
  std::vector<std::string> make_f2fs_cmd = {
    "/system/bin/make_f2fs",
    "-g",
    "android",
  };
  if (needs_projid) {
    make_f2fs_cmd.push_back("-O");
    make_f2fs_cmd.push_back("project_quota,extra_attr");
  }
  if (needs_casefold) {
    make_f2fs_cmd.push_back("-O");
    make_f2fs_cmd.push_back("casefold");
    make_f2fs_cmd.push_back("-C");
    make_f2fs_cmd.push_back("utf8");
  }
  if (v->fs_mgr_flags.fs_compress) {
    make_f2fs_cmd.push_back("-O");
    make_f2fs_cmd.push_back("compression");
    make_f2fs_cmd.push_back("-O");
    make_f2fs_cmd.push_back("extra_attr");
  }
  make_f2fs_cmd.push_back(v->blk_device);
  if (length >= kSectorSize) {
    make_f2fs_cmd.push_back(std::to_string(length / kSectorSize));
  }

  if (exec_cmd(make_f2fs_cmd) != 0) {
    PLOG(ERROR) << "format_volume: Failed to make_f2fs on " << v->blk_device;
    return -1;
  }
  if (!directory.empty()) {
    std::vector<std::string> sload_f2fs_cmd = {
      "/system/bin/sload_f2fs", "-f", directory, "-t", volume, v->blk_device,
    };
    if (exec_cmd(sload_f2fs_cmd) != 0) {
      PLOG(ERROR) << "format_volume: Failed to sload_f2fs on " << v->blk_device;
      return -1;
    }
  }
  return 0;
}

int format_volume(const std::string& volume) {
  return format_volume(volume, "");
}

int setup_install_mounts() {
  if (fstab.empty()) {
    LOG(ERROR) << "can't set up install mounts: no fstab loaded";
    return -1;
  }
  for (const FstabEntry& entry : fstab) {
    // We don't want to do anything with "/".
    if (entry.mount_point == "/") {
      continue;
    }
    // HUANGLONG begin
    // recovery, Add the /sdcard and /data mount points.
    if (entry.mount_point == "/tmp" || entry.mount_point == "/cache" || entry.mount_point == "/sdcard" || entry.mount_point == "/data") {
    // HUANGLONG end
      if (ensure_path_mounted(entry.mount_point) != 0) {
        LOG(ERROR) << "Failed to mount " << entry.mount_point;
        // HUANGLONG begin
        // return -1;
        // HUANGLONG end
      }
    } else {
      if (ensure_path_unmounted(entry.mount_point) != 0) {
        LOG(ERROR) << "Failed to unmount " << entry.mount_point;
        return -1;
      }
    }
  }
  return 0;
}

bool HasCache() {
  CHECK(!fstab.empty());
  static bool has_cache = volume_for_mount_point(CACHE_ROOT) != nullptr;
  return has_cache;
}